Method and apparatus for adding yarn ends



Aug. 18, 1953 R. c. POLLMAN METHOD AND APPARATUS FOR ADDING'YARN ENDS Filed June 2, 1652 2 Sheets-Sheet 1 INVENTOR RALPH CIPOLLMAN ATTORNEY A g. 18, 1953 R. C.'POL.LMAN 2,648,891

'METHOD AND APPARATUS FOR ADDING YARN ENDS Filed June 2, 1952 2 Sheets-Sheet 2 INVENTOR RALPH C. POLLMAN ATTORNEY Patented Aug. 18, 1953 METHOD AND APPARATUS FOR ADDING YARN ENDS Ralph C. Pollman, Seaford, Del., assignor to E. I.

du Pont de Nemours and Company, Wilmington, Del., a corporation of Delaware Application J une 2, 1952, Serial No. 291,099

4 Claims. (01. 2871.5)

This invention relates to an apparatus for combining running ends of yarn to form a tow or rope of yarn, and is more particularly concerned with an apparatus for adding an end of yarn to moving yarns without interrupting the movement of the yarn.

In the production of staple fiber, yarns from several creel or spinning positions may be combined into a large bundle called a tow or rope. The tow is frequently a more convenient form in which to handle the fibers during aftertreatment, including that of cutting into short lengths called staple. The addition of an end of yarn to moving yarn or tow is relatively easy when the yarns are wet, as the water causes the yarns to adhere. Dry hydrophillic yarns, such as acetate rayon yarns, can be combined by sponging in, i. e., the yarns are wetted to cause them to adhere. However, certain of the new synthetic fibers do not wet easily and it is diificult to add a yarn end to running yarn or tow without interrupting movement of the yarn.

Accordingly, it is an object of the present invention to provide an apparatus which is effective and convenient for adding a yarn end to running yarn or tow, regardless of the condition and type of yarn, and without interrupting movement of the running yarn or tow. Other objects of the invention will become apparent from the following description, the accompanying drawing and the claims.

In accordance with the present invention, a mechanical false twister is used to wind a yarn end about a running yarn or tow and guide the added end against a cutter to trim off the free end. The false twister preferably produces a twist by means of a plurality of skew elements which are mounted to be swung into engagement with the running yarn or tow. With these elements in the disengaged position, the yarn or tow and the end to be added are guided between the elements without twist being imparted. The elements are then swung into position to engage the running yarn at successive positions and cause it to rotate. The free end is held and, therefore, is wound about the running yarn. The surplus end is then cut off next to the yarn or tow by a suitable cutter.

In the drawings, which illustrate a preferred embodiment of the invention,

Figure 1 is a plan view of an apparatus in accordance with the invention, with the twist-producing elements in the disengaged position,

Figure 2 is a corresponding plan view with the elements swung into operating position,

Figure 3 is a front elevation of the apparatu shown in Figure 2, and

Figure 4 is an elevation of one of the false twister elements.

Referring now to Figure 1, it is seen that the apparatus is so positioned that a tow or rope ID of yarn can proceed in an unobstructed straight line along the line A-A when the apparatus is in this disengaged position. False twister elements H and I2, together with the cutting device 53, are rigidly afiixed to movable plate I5 which pivots at bearing i 6 near the center of base plate ll. Handle 18, likewise rigidly connected to plate I5, is used to move the apparatus into and out of the engaged position. False twister element is is movably mounted on baseplate [1, being rigidly attached to shaft 20 which pivots in bearing 2! and is rigidly connected to crank arm 22. In turn plate It is rigidly connected to crank arm 23 through shaft 24 passing through bearing it. These two crank arms are interconnected through arm 26 so that movement of plate ill by handle I8 moves twister element I!) through an equal angle in the opposite direction.

To operate the apparatus, a yarn end 30 which is to be tied into the moving tow is brought along line A A of Figure 1 to the middle false twister element l2, passed around this element, and then is pulled continuously back in the direction from which it came by suitable means, as with an aspiratin device. Other means such as winding on a Waste spool or even hand-over-hand pulling can be used to keep the yarn end reasonably taut and traveling at a speed comparable to that of the tow l 0.

The handle i8 is now swung through to the position shown in Figure 2. This turns the false twisting elements into position to engage the tow. The yarn end and the tow now pass together in contact with false twisters I l and I2, and the tow continues by itself to contact false twister l9 and pass on to the next operation. The yarn end 36 leaves the tow after passage through false twister l2 and is pulled away in front of cutting device I3. The free false twisters are all arranged to twist the tow in the same direction; as illustrated they will cause the tow to rotate in a counter-clockwise direction when lookin in the direction of tow travel. Since the end of yarn is held, it will be Wound around the rotating tow and secured in place. Immediately thereafter the travelling tow will pull the yarn end against the cutting device l3 and surplus yarn will be trimmed off close to the tow. The added yarn end will then travel along with the 3 tow. The false twisting elements are now disengaged from the tow by throwing handle [8 back to the original position of Figure 1. Additional yarn ends may be added by repeating the above operation.

The cutting device I3 is indicated in the drawin -s as an electric hair clipper. Preferably this is a clipper of the animal haircutting type;- However, a variety of cutting devices can obviously be used. A simple cutting edge, such as a razor blade, will sometimes serve for thfiepl rnoset The false twisting elements can be of various; types. Those shown in the drawings utilize the principle that a yarn drawn at an -obl ique angleover a guide will be causedto twist: A'-ppi-nt;;on-- the yarn surface contacting the guide surface will be pushed to one side in aedirdstiqn whiqhr, tends to cause the point to move parallel to the guide surface. Since this force is not balancedby the effect of a contacting surface on the other sideof the yarn, ail-unbalanced torqueisproduced which twists the yarn.-

Asshown in Figure-=3, thetow- 10 :moves horizontally from right to left in frontofg-uiding surface 3lof false twister l L This surface 31 is slantedupward to the left-atan angle-ofabout to the hor-iaontaL Hencethe far side of the tow, whereit contacts this-surface,- is moved up-- ward and the towistwisted. in l a counter-c1ockwise direction when viewedwvi-th the tow travellingaway from the observer as shownin Figure l The tow next passes horizontally behind-the guidingsuriaceBZ of the-second false twister l2, and this surface is-slanted upward to the right at a nangle-of abOut-BO -to the-horizontal. Hence the near side of the tow, where it contacts this surface-is moved downwardand the tow. is again twisted in- I a counter-clockwise direction. The last-'false-twistings element Isis-similar to and engages the-tow. inthe same manner as the first element llp The towpassing in front of the oblique guiding surface-33is again twisted ina counter-clockwise direction. The effect of these. three false twisters acting toapply twist in the same directionistoimpart an 'S-twist to thetow approaching-the apparatus, and an equal and opposite z-twist-to the-towleavingthe apparatus, as'indicated in- Figurei:

Figure-4 shows a few more details of the type of false-twisting element used in this preferred embodiment; Triangular projections 35- and- 36 serve to direct the'towintoposition on theoblique guidingsurface 3h The-portions of these-sur-- faces which: contact the-toware made round and smooth to avoid damaging the tow fibers. The falsetwistersis provided with a right-angle-flange at-the bottom for-mounting theelement onplate 15 Although the-description of the operation of the device has-dealtwith the tying-in of a free endof yarn into a running end oftow, the invention isequallyapplicable to the-tying-in-of a plurality of freeendsof yarn into a-runni-ng end of tow; Usually thetow Will -comprise awlarge 4 number of ends of yarn, e. g., from 40 to 50, up to several hundred, with the result that the total denier of the tow may vary between rather wide limits, 1. e., from 2 to 3 thousand, up to 2 to 3 million or even more.

While the invention has been described in terms of a preferred embodiment'thereof, it is apparent-that many different embodiments may be made without departing from the spirit or the scope of the invention and it is to be understood that the invention. is not limited by the specific illustrations except to the extent defined in the following claims.

What is-claimed is:

1. A method-for adding a yarn end to running yarnwhich comprises guiding running yarn and ayarrrend together to form a tow and then guiding the free end of yarn away from the running yarn;- rotating the tow so that the yarn end is Wrapped around the running yarn, and immediately'thereafter' cutting. off. the. free endof added yarn'close to the tow.-

2. An apparatus for :addinga yarn endto'rum.

, n-ingyarnincluding in combination a mechanical false-twister adapted to bring running yarrrand a yarn end together to form a tow andathenrotate the tow, means for guiding the free end .of yarnaway from the tow at: said false twister so that rotation of the towwill'wrap the yarn end about the tow, and cutting, means located ad-. jacent to said false twister: in. position to cut off the free end of yarn as. soon as. the. yarn end is;

wrapped about the tow.v

3. An apparatusforadding. ayarn'endto running. yarn including in combinationa false twister comprising a plurality of skew elements arranged to engage running. yarn at successive positions and cause the. yarn to .rotate, meansforv guiding a free end of yarn away from the, running yarn ata point between two of said skew'elements, and cutting means located adjacent to. said: guiding means in position to cut off the free end of yarn close to the running yarn.

4, An apparatusfor adding ayam end tourunning yarn including in combination-a plurality of skew elements mounted to be swung. into::en-: gagementwith running yarn, .said elements be-. ing arranged to. contact the runninglzyarn at oblique-angles at successive positions and cause the: yarn to rotate in the same. direction; means for guiding a free endof yarnvaway. from the. runningyarn at .a point between .two of said skew elements, andan automatic clipper adapted to cut off the free end .of .yarn close to: the running 4 yarn-between said guiding means and the immediately subsequent skew. element.

RALPHJC. POLLMAN;

References Citedin the; file Of this patent UNITED STATES" PATENTS Number 1 

